Project Summary/Abstract Current pre-operative and intraoperative margin assessment techniques fail to adequately guide breast cancer surgeons to remove all cancer during breast conserving surgeries. As a result, 20-40% of lumpectomy patients have unrecognized tumor left in the tumor bed during the initial surgery. This residual tumor is only discovered when the pathologist evaluates the resection margins after surgery and finds a positive margin. The majority of patients with positive margins (~87%) require a second surgery, which increases health care costs along with patient anxiety and discomfort. To address this unmet need, Lumicell has developed an intraoperative imaging system consisting of a molecular imaging agent (LUM015) that emits fluorescence after activation by cancer associated enzymes, a compact hand-held imaging head (LUM 2.6 Device) that captures the fluorescence emission of the agent and software that detects and displays invasive carcinomas (80% of the breast cancer cases) in real-time to guide the surgeon. We, at the Massachusetts General Hospital, are conducting a feasibility study in breast cancer patients under an FDA-approved IDE. The first part of the feasibility study has been completed with no adverse events observed in 15 patients. Initial results from the feasibility study show no false negatives (100% sensitivity) with ~10% false positives. During this study, an approach for detecting the much smaller foci of ductal carcinoma in situ (DCIS; 20% of breast cancer cases) was developed. As the first aim of this proposal, the team will develop and implement software for real-time detection of DCIS. The second aim is a two arm, multi-institution pivotal clinical trial in support of our PMA application to measure the efficacy of the LUM Imaging System. The primary endpoint of the study is the reduction in positive margin rates for surgeries in which the LUM Imaging System is used versus standard of care (SOC) treatment for breast cancer patients undergoing breast conserving lumpectomies. The secondary endpoint is a reduction in the rate of second surgeries for positive margins when the LUM Imaging System is used. The two arms of the study will consist of a control arm and a device arm. The control arm will include 100 patients, while the device arm will include 300 patients. In the control arm, patients will undergo a routine lumpectomy procedure. In the device arm, patients will undergo a routine lumpectomy procedure followed by imaging of the lumpectomy cavity with the LUM Imaging System. Additional therapeutic cavity shaves will be removed from regions that LUM Imaging System determines to contain cancer.